Add an error management in db module

[recipes.git] / backend / src / db.rs

diff --git a/backend/src/db.rs b/backend/src/db.rs
index a4a0d97..ac97f1b 100644 (file)
--- a/backend/src/db.rs
+++ b/backend/src/db.rs
@@ -11,6 +11,12 @@ use std::fs;
 use r2d2_sqlite::SqliteConnectionManager;\r
 use r2d2::Pool;\r
 \r
+#[derive(Debug)]\r
+pub enum DbError {\r
+    SqliteError(rusqlite::Error),\r
+    R2d2Error(r2d2::Error),\r
+    UnsupportedVersion(i32),\r
+}\r
 \r
 use super::consts;\r
 \r
@@ -26,8 +32,20 @@ pub struct Recipe {
     pub id: i32,\r
 }\r
 \r
+impl std::convert::From<rusqlite::Error> for DbError  {\r
+    fn from(error: rusqlite::Error) -> Self {\r
+        DbError::SqliteError(error)\r
+    }\r
+}\r
+\r
+impl std::convert::From<r2d2::Error> for DbError  {\r
+    fn from(error: r2d2::Error) -> Self {\r
+        DbError::R2d2Error(error)\r
+    }\r
+}\r
+\r
 impl Connection {\r
-    pub fn new() -> Connection {\r
+    pub fn new() -> Result<Connection, DbError> {\r
 \r
         let data_dir = Path::new(consts::DB_DIRECTORY);\r
 \r
@@ -39,59 +57,83 @@ impl Connection {
         let pool = r2d2::Pool::new(manager).unwrap();\r
 \r
         let connection = Connection { pool };\r
-        connection.create_or_update();\r
-        connection\r
+        connection.create_or_update()?;\r
+        Ok(connection)\r
     }\r
 \r
-    fn create_or_update(self: &Self) {\r
+    /*\r
+     * Called after the connection has been established for creating or updating the database.\r
+     * The 'Version' table tracks the current state of the database.\r
+     */\r
+    fn create_or_update(self: &Self) -> Result<(), DbError> {\r
         // let connection = Connection::new();\r
         // let mut stmt = connection.sqlite_con.prepare("SELECT * FROM versions ORDER BY date").unwrap();\r
-        // let mut stmt = connection.sqlite_con..prepare("SELECT name FROM sqlite_master WHERE type='table' AND name='versions'").unwrap();\r
+        // let mut stmt = connection.sqlite_con.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name='versions'").unwrap();\r
 \r
         // Check the Database version.\r
-        let con = self.pool.get().unwrap();\r
+        let mut con = self.pool.get()?;\r
+        let tx = con.transaction()?;\r
 \r
-        let version = {\r
-            match\r
-                con.query_row(\r
+        let mut version = {\r
+            match tx.query_row(\r
                     "SELECT [name] FROM [sqlite_master] WHERE [type] = 'table' AND [name] = 'Version'",\r
-                    rusqlite::NO_PARAMS,\r
-                    |row| row.get::<usize, String>(0)\r
-                ) {\r
-\r
-                Ok(_) => con.query_row("SELECT [version] FROM [Version]", rusqlite::NO_PARAMS, |row| row.get(0)).unwrap_or_default(),\r
+                        rusqlite::NO_PARAMS,\r
+                        |row| row.get::<usize, String>(0)\r
+                    ) {\r
+                Ok(_) => tx.query_row("SELECT [version] FROM [Version]", rusqlite::NO_PARAMS, |row| row.get(0)).unwrap_or_default(),\r
                 Err(_) => 0\r
             }\r
         };\r
 \r
+        while Connection::update_to_next_version(version, &tx)? {\r
+            version += 1;\r
+        }\r
+\r
+        tx.commit()?;\r
+\r
+        Ok(())\r
+    }\r
+\r
+    fn update_to_next_version(version: i32, tx: &rusqlite::Transaction) -> Result<bool, DbError> {\r
         match version {\r
             0 => {\r
                 println!("Update to version 1...");\r
-                con.execute(\r
+\r
+                // Initial structure.\r
+                tx.execute_batch(\r
                     "\r
                     CREATE TABLE [Version] (\r
                         [id] INTEGER PRIMARY KEY,\r
-                        [version] INTEGER NOT NULL,\r
+                        [version] INTEGER NOT NULL UNIQUE,\r
                         [datetime] INTEGER DATETIME\r
-                    )\r
-                    ",\r
-                    rusqlite::NO_PARAMS\r
-                );\r
-                con.execute(\r
-                    "\r
+                    );\r
+\r
                     CREATE TABLE [Recipe] (\r
                         [id] INTEGER PRIMARY KEY,\r
                         [title] INTEGER NOT NULL,\r
                         [description] INTEGER DATETIME\r
-                    )\r
+                    );\r
+                    "\r
+                )?;\r
+\r
+                /*\r
+                tx.execute(\r
+                    "\r
+                    INSERT INTO Version\r
                     ",\r
                     rusqlite::NO_PARAMS\r
-                );\r
-                ()\r
+                );*/\r
+\r
+                Ok(true)\r
             }\r
+\r
+            // Current version.\r
+            1 =>\r
+                Ok(false),\r
+\r
             v =>\r
-                panic!("Unsupported database version: {}", v)\r
-        };\r
+                Err(DbError::UnsupportedVersion(v)),\r
+        }\r
     }\r
 \r
     pub fn get_all_recipes() {\r